--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/org.chromium.debug.ui/src/org/chromium/debug/ui/actions/CompareChangesAction.java	Mon Jun 07 16:51:19 2010 -0700
@@ -0,0 +1,86 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.debug.ui.actions;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.lang.reflect.InvocationTargetException;
+
+import org.chromium.debug.core.model.VmResource;
+import org.eclipse.compare.CompareConfiguration;
+import org.eclipse.compare.CompareEditorInput;
+import org.eclipse.compare.CompareUI;
+import org.eclipse.compare.IModificationDate;
+import org.eclipse.compare.IStreamContentAccessor;
+import org.eclipse.compare.ITypedElement;
+import org.eclipse.compare.structuremergeviewer.DiffNode;
+import org.eclipse.compare.structuremergeviewer.Differencer;
+import org.eclipse.core.resources.IFile;
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.swt.graphics.Image;
+
+/**
+ * A very preliminary implementation of action that should let user compare his script with
+ * its current state on remote VM.
+ */
+public class CompareChangesAction extends V8ScriptAction {
+  @Override
+  protected void execute(FilePair filePair) {
+    LiveEditCompareInput input = new LiveEditCompareInput(filePair.getFile(), filePair.getVmResource());
+    CompareUI.openCompareEditor(input);
+  }
+
+  private static class LiveEditCompareInput extends CompareEditorInput {
+    private final IFile file;
+    private final VmResource script;
+
+    LiveEditCompareInput(IFile file, VmResource vmResource) {
+      super(createCompareConfiguration());
+      this.file = file;
+      this.script = vmResource;
+    }
+
+    private static CompareConfiguration createCompareConfiguration() {
+      return new CompareConfiguration();
+    }
+
+    @Override
+    protected Object prepareInput(IProgressMonitor monitor) throws InvocationTargetException,
+        InterruptedException {
+
+      abstract class CompareItem implements ITypedElement, IStreamContentAccessor,
+          IModificationDate {
+        public Image getImage() {
+          return null;
+        }
+        public String getType() {
+          return TEXT_TYPE;
+        }
+        public long getModificationDate() {
+          return 0;
+        }
+      }
+      CompareItem left = new CompareItem() {
+        public String getName() {
+          return "Local file " + file.getName(); //$NON-NLS-1$
+        }
+        public InputStream getContents() throws CoreException {
+          return file.getContents();
+        }
+      };
+      CompareItem right = new CompareItem() {
+        public String getName() {
+          return "File in VM " + script.getFileName(); //$NON-NLS-1$
+        }
+        public InputStream getContents() throws CoreException {
+          return new ByteArrayInputStream(script.getScript().getSource().getBytes());
+        }
+      };
+      DiffNode diffNode = new DiffNode(null, Differencer.PSEUDO_CONFLICT, null, left, right);
+      return diffNode;
+    }
+  }
+}